1. Field of the Invention
The present invention relates to a suture and ligature device for medical treatment that is used together with an endoscope in endoscopy treatments such as the suturing or ligaturing of biological tissue in a patient.
Priority is claimed on Japanese Patent Application Nos. 2005-151195, filed May 24, 2005 and 2005-264816, filed Sep. 13, 2005, the contents of which are incorporated herein by reference.
2. Description of Related Art
Among suture and ligature devices for medical treatment that suture or ligature biological tissue in a patient under endoscopic observation there are those that have a sheath that is able to be inserted into the channel of an endoscope, an operating wire that is inserted into the sheath such that it can move freely forwards and backwards, and a ligature tool for medical treatment that is engaged with a hook that is fixed to a distal end of the operating wire.
This ligature tool for medical treatment has a ligature wire in the form of a loop, and a stopper through which the ligature wire is press-inserted. The size of the loop can be adjusted by moving the stopper forwards or backwards along the ligature wire. When a lesion portion is being ligatured, the loop is first placed around the lesion portion. Next, the hook is moved backwards and the stopper is pushed forward relatively towards the lesion portion, thereby reducing the diameter of the loop, and tightly binding the lesioned portion. After this, the ligature wire is cut between the portion that is binding the lesioned portion and the portion that is engaged with the hook, and the ligature wire is left in the patient in a state of ligaturing the biological tissue.
Here, in order that the operation to bind and ligature a lesioned portion using a medical ligature tool and the operation to cut the ligature wire can be performed in successive operations, a cutting member that has a blade portion is provided on the outside of the sheath through which the hook is inserted such that it can move freely backwards and forwards. In addition, a wire holding member that receives the cutting member while holding the ligature wire is provided on the medical ligature tool between the portion that is engaged with the hook and the stopper (see, for example, Patent Document 1: Japanese Unexamined Patent Application, First Publication No. 2003-204966). The blade portion of the cutting member in this case is provided at a right angle to the direction of forward movement of the cutting member. When the blade portion cuts a ligature wire that has been pulled to the outside through a side hole in the wire holding member, the cutting blade makes contact at a right angle to the axial direction of the wire holding member, and the cut is made with the ligature wire sandwiched between the holding member and the cutting blade.